This is a proposal for a cross-sectional study of the social relationships of 400 gay and bisexual men at risk for AIDS. The study will examine four major questions: (1) What features of social relationships are most conducive to psychological health and AIDS-preventive behavior among gay and bisexual men; (2) What social skills and communication styles are associated with support and conflict in the personal network; (3) What type of relationship--a primary sexual relationship, or other friendships in the network--has the greater impact on AIDS-preventive behavior and psychological health; and (4) What special features of primary relationship--such as intimacy, affirmation, and commitment--can facilitate AIDS-preventive behavior and psychological health. This study will emphasize the experiences of social relationships that pertain specifically to the AIDS/HIV epidemic. Previous research on social support has been more successful at explaining psychological health than at explaining AIDS-preventive behavior among members of this risk population. By directly addressing the AIDS-related experiences of social relationships, this study will attempt to establish stronger associations between social predictors and behavioral outcomes. Questionnaire data will be collected from gay and bisexual men in the Portland, Oregon, metropolitan area. These men will be recruited through the local gay community and "snowball" contacts. The questionnaire has been piloted for use in this population. Regression analyses will attempt to explain the features of social relationships and the social skills that facilitate psychological health and AIDS-preventive behavior among members of this risk group.